One obstacle encountered in integrating electrical devices with optical components on a wafer level is how to manage the electrical connections. Typical wafer assembly and separating can yield an excellent optical assembly, but with no feasible location for electrical connections, as shown in FIG. 1. In FIG. 1, the module includes an active element 10 mounted on a submount 20 and an optics block 30 with an optical element 40 thereon. Interconnection lines 22 are formed on the submount 20 to provide electrical signals to and/or from the active element 10. The active element 10, e.g., a vertical cavity surface emitting laser (VCSEL), can bonded to the submount 20 at the wafer level, optics and any spacers aligned thereto and integrated therewith. When the individual modules are separated, the electrical connections 22 to the active element 10 are difficult to access.
Another problem arises when attempting to integrate optical element elements formed on a wafer level with planar systems, such as a printed circuit board, or any system which is not to continue the stacked structure of the wafer level constructions. Support and alignment are both issues in this integration.
One potential solution is to assemble the optics and spacers at the wafer level, then separate and bond to the individual submounts. However, this does not take full advantage of wafer level assembly.